Unconscious products of the imagination (6)

I believe the answer is:

dreams

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'imagination' is the definition.
(I know this)

I don't understand the rest of the clue.

(Other definitions for dreams that I've seen before include "Reveries or cherished aspirations" , "Imaginings" , "'''We are such stuff as ... are made on'' The Tempest (6)'" , "Thoughts and visions during sleep" , "Fantasies; fantasises" .)

I've seen this clue in the Evening Standard.

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